On Wed, Mar 24, 2021 at 10:22:54AM +0300, Dan Carpenter wrote: > Hello Ville Syrjälä, > > This is a semi-automatic email about new static checker warnings. > > The patch 97bc7ffa1b1e: "drm/i915: Fix enabled_planes bitmask" from > Mar 5, 2021, leads to the following Smatch complaint: > > drivers/gpu/drm/i915/display/intel_atomic_plane.c:332 intel_plane_atomic_check_with_state() > error: we previously assumed 'fb' could be null (see line 324) > > drivers/gpu/drm/i915/display/intel_atomic_plane.c > 323 > 324 if (fb) > ^^ > The patch adds a check for NULL > > 325 new_crtc_state->enabled_planes |= BIT(plane->id); > 326 > 327 /* FIXME pre-g4x don't work like this */ > 328 if (new_plane_state->uapi.visible) > 329 new_crtc_state->active_planes |= BIT(plane->id); > 330 > 331 if (new_plane_state->uapi.visible && > 332 intel_format_info_is_yuv_semiplanar(fb->format, fb->modifier)) > ^^^^^^^^^^^^^^^^^^^^^^^^ > Unchecked deref > > 333 new_crtc_state->nv12_planes |= BIT(plane->id); > 334 > 335 if (new_plane_state->uapi.visible && > 336 fb->format->format == DRM_FORMAT_C8) > ^^^^^^^^^^ > Same. These are potentially false positives. I don't know if > "uapi.visible" can be true when ctrc is non-NULL and fb is NULL for > example? (The point is I read the commit message, but I know pants all > about DRM. :P) If there's no fb then uapi.visible=false. See intel_atomic_plane_check_clipping(). > > 337 new_crtc_state->c8_planes |= BIT(plane->id); > 338 > 339 if (new_plane_state->uapi.visible || old_plane_state->uapi.visible) > 340 new_crtc_state->update_planes |= BIT(plane->id); > 341 > 342 new_crtc_state->data_rate[plane->id] = > 343 intel_plane_data_rate(new_crtc_state, new_plane_state); > 344 > 345 return intel_plane_atomic_calc_changes(old_crtc_state, new_crtc_state, > 346 old_plane_state, new_plane_state); > 347 } > > regards, > dan carpenter -- Ville Syrjälä Intel _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
